Chest Wall EMG during Postural Stability
Tasks and Vocalization in Infants and Young Children With and Without Neurogenic
Communication DisordersCarol Boliek, Leila Homaeian, Charene Welsh, Reza Sherkat

This study was designed to provide new and exploratory data
on muscle activation patterns of the chest wall during phonation and speech
in infants and young children with and without neurogenic communication disorders.
The specific aim of this research was to characterize the interplay of shared
muscle groups in the production of speech, breathing, and the maintenance of
posture. This presentation reports on our mesurement and analysis protocol which
was adapted from Grosse, Cassidy, and Brown, 2002. Frequency, coherence, and
phase difference analyses of EMG signals were conducted on selected pairings
of rib cage and abdominal muscle groups during speech and nonspeech tasks performed
across a variety of static postural pertubations. Coherence and phase measurements
on EMG signals revealed various patterns of oscillatory coupling between intermuscular
motor elements. Our analyses were sensitive to differences in muscle activation
patterns among healthy adults, chidren, and infants as well as patterns from
children with cerebral palsy. Results allowed us to make inferences about descending
cortical and subcortical motor drive. Ultimately this line of inquiry will ultimately
provide a comprehensive physiological analysis of chest wall behavior during
breathing, vocalization, and postural control in children with and without neurogenic
communication disorders.